In areas where the Jori-system (a kind of township in old Japan) still exists, the term “Aza” is used to mark sections of the field. “Aza” usually corresponds with “Tsubo” which is the smallest unit of “Ri”.
Each section of “Aza” is usually irregular Blockflur, but in the areas where the Jori-system still exists the strips are regular Streifenflur (about 13m×130m) and is similar to Kruzstreifenflur, according to G. Niemeier's classification of field patterns.
The type of field corresponding to Langstreifenflur, Which is the oldest type of field found in Germany according to him, are not found in Japan.
The strips of Jori have frequently been changed into Block-flur during the years with the redistribution of land.
Gewann and Feld were regional units which controlled communal land ownership and agricultural operation (in Germany). As for “Aza” in Japan, in paddy fields requiring irrigation, strips in the same “Aza” were and still are frequently irrigated by the same irrigation canal. The smallest group of people engaged in rice-planting or irrigation is formed among farmers who have paddy-fields in the same “Aza” rather than among neighbors.
If we look at a section in the old Chinese Seiden system, which is a prototype of the Japanese Jori-system, we see that this section is a square which eight families cultivated, and one unit with the same communal controls for irrigation and cultivation.
The writer would take “Aza” and Gewann for the smallest unit of the regior, ecotop. However, in contrast to Gewann and Feld in the three field system of western Europe, “Aza” has played no regional function as a unit of property allocation.